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Horizontal Positioning not available in Street Placement?

January 21 2011 | 6 comments
Categories: Labeling, Maplex

I want to force my road symbols to be horizontally placed, but without the Road Placement algorithm in place, they are placed way too frequently, despite my "Repeat Label" being engaged. There is, however, no horizontal placement function in Street Placement. So it seems I have to choose between way to frequent symbol placement or crooked placement. How can I mitigate this? Thank you!

Mapping Center Answer:

I was able to reproduce what you were seeing, and used a repeat labels setting for Maplex of 4 inches.  In order to get highway shields to work properly, you will also need a complementary Remove Duplicates setting that is just under 4 inches (I used 3.5 inches and it worked well).  Also don't do like I did the first time and forget to change the units to inches (from the default of map units).

So that should resolve the frequent placement issue.  That said, the use of 4 inches as a general spacing is something that will vary with map scale, and to some extent with respect to the number of characters in the label for the interstate or road shield.  Basically the fewer the characters, the longer the segments tend to be and therefore the need for repetition is less.  But for routes that are generally shorter, participating in complex closely spaced interchanges, it is important to label each segment of the route at least once, so you'll want a shorter repeat labels and remove duplicates setting.   The way to do that is to create two label classes, where the differentiator is SQL queries that use SQL CHAR_LENGTH function, and these would look like:  

"Type" = 'Interstate' AND CHAR_LENGTH( "LabelField") > 2

"Type" = 'Interstate' AND CHAR_LENGTH( "LabelField") <= 2

This will allow you to independently apply the distances.  The CHAR_LENGTH 

Last, a little bit about the Street Placement setting in Maplex:  It was designed to facilitate labeling surface streets and to be intelligent about contiguity and laddering street names along adjacent parallel sets of streets, so they look nice.  We didn't, therefore name it "Road Placement", leading people to expect it to do special things with route labels like we are discussing.  So, you were on the right track, and this should be what you need to finish.



RE: Horizontal Positioning not available in Street posted by Marianne Farretta on Jan 27 2011 8:41AM
I'm not sure I understand; are you suggesting there is a relationship between a state route's designated number and the road's actual length? And "Street Placement" is meant to understand contiguity by recognizing those segments which share end/beginning points as the same, so shouldn't that prevent my CC215 symbol from being placed within the four inch Remove Dupes I have commanded? Street Placement does seem to work that way; it successfully places my labels without unnecessary repetition--the only problem is that it rotates the symbol, instead of maintaining a horizontal placement, as is available with the Regular Placement. This is the root of my question; can it be helped? Thank you!
It's about scale posted by Charlie Frye on Jan 27 2011 9:45AM
The point was that at a given map scale, the some routes will be shorter than your remove duplicates distance. When such routes are intersected by other routes (as often happens in urbanized or populated areas), you need to get a label on both sides of the intersection so that the map will be unambiguous. It is best to presume that the more characters in the route, the shorter it generally is. Look at a road map with this in mind and you'll see that this generally holds true. That said, I was thinking specifically of Interstates and U.S. Routes. State or county routes are as likely to follow such a convention.
RE: It's about scale posted by Marianne Farretta on Jan 27 2011 9:47AM
I would like to submit another jpg for your review on this same topic, but the comments window don't support this--may I submit via another venue, email maybe?
Add a new question... posted by Charlie Frye on Jan 27 2011 9:50AM
Then copy and paste the URL for this one in as a link to show that they are related. Then I'll add a link in this one's response to see more.
Oh Duh (my fault) posted by Charlie Frye on Jan 27 2011 9:52AM
I failed to respond to your last question in the the first comment.

Maplex's street placement option does not do highway shield placement. These are fundamentally different problems, and don't have the same solution.
URL posted by Marianne Farretta on Jan 27 2011 10:00AM

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